gcc: deduplicate boilerplate

This commit deduplicates libgcc-related boilerplate which appears in
every version of our gcc expression, by moving it into libgcc.nix.

I will be submitting a separate PR which changes this boilerplate,
but that PR will be much easier to review if I can make the change
in just one place.

Meanwhile, *this* commit has no effect on eval:

$ for A in 10  11  12  13  4.8  4.9  6  7  8  9; do nix-instantiate . -A gcc$(echo $A | tr -d .); done 2>/dev/null | sort | tee before
/nix/store/1a37lnzpnz0dhm3lphiy2gcdrxgqa7ma-gcc-wrapper-4.8.5.drv
/nix/store/5szdivc8il0c3g94dq4wqnq5j77a9h6p-gcc-wrapper-11.4.0.drv
/nix/store/bmmc717wmnp1j2xkd3if5dfxicnflvn5-gcc-wrapper-7.5.0.drv
/nix/store/fc1ggpixv3wqcazchhl2hnn5zl5ds30l-gcc-wrapper-13.1.0.drv
/nix/store/j9c2b20w35r3ag5nxmklhagbwsgjhds2-gcc-wrapper-4.9.4.drv
/nix/store/nq7q57bxmsk2g457wr4b9449as3f216w-gcc-wrapper-12.3.0.drv
/nix/store/sqmkkfapzykapcs4azvxm83n786ga7q1-gcc-wrapper-10.4.0.drv
/nix/store/vxnz30i23mkl4ldsq485kxn7q0p2y4nf-gcc-wrapper-8.5.0.drv
/nix/store/yfhv0bv15cg5kj2xsb9fcgb6pdlw42v0-gcc-wrapper-6.5.0.drv
/nix/store/yi5gr75pb6kddnll10jg25hhndhkba7s-gcc-wrapper-9.5.0.drv

$ for A in 10  11  12  13  4.8  4.9  6  7  8  9; do nix-instantiate . -A gcc$(echo $A | tr -d .); done | sort | tee after
/nix/store/1a37lnzpnz0dhm3lphiy2gcdrxgqa7ma-gcc-wrapper-4.8.5.drv
/nix/store/5szdivc8il0c3g94dq4wqnq5j77a9h6p-gcc-wrapper-11.4.0.drv
/nix/store/bmmc717wmnp1j2xkd3if5dfxicnflvn5-gcc-wrapper-7.5.0.drv
/nix/store/fc1ggpixv3wqcazchhl2hnn5zl5ds30l-gcc-wrapper-13.1.0.drv
/nix/store/j9c2b20w35r3ag5nxmklhagbwsgjhds2-gcc-wrapper-4.9.4.drv
/nix/store/nq7q57bxmsk2g457wr4b9449as3f216w-gcc-wrapper-12.3.0.drv
/nix/store/sqmkkfapzykapcs4azvxm83n786ga7q1-gcc-wrapper-10.4.0.drv
/nix/store/vxnz30i23mkl4ldsq485kxn7q0p2y4nf-gcc-wrapper-8.5.0.drv
/nix/store/yfhv0bv15cg5kj2xsb9fcgb6pdlw42v0-gcc-wrapper-6.5.0.drv
/nix/store/yi5gr75pb6kddnll10jg25hhndhkba7s-gcc-wrapper-9.5.0.drv

$ diff -u after before
$

1 files changed, 5 insertions, 5 deletions

diff --git a/pkgs/development/compilers/gcc/9/default.nix b/pkgs/development/compilers/gcc/9/default.nix
index 53c98a0b7a8..d022349c73a 100644
--- a/pkgs/development/compilers/gcc/9/default.nix
+++ b/pkgs/development/compilers/gcc/9/default.nix
@@ -26,6 +26,7 @@
 , gnused ? null
 , cloog # unused; just for compat with gcc4, as we override the parameter on some places
 , buildPackages
+, callPackage
 }:
 
 # Note: this package is used for bootstrapping fetchurl, and thus
@@ -143,7 +144,7 @@ let majorVersion = "9";
 
 in
 
-stdenv.mkDerivation ({
+lib.pipe (stdenv.mkDerivation ({
   pname = "${crossNameAddon}${name}";
   inherit version;
 
@@ -287,10 +288,9 @@ stdenv.mkDerivation ({
   };
 }
 
-// optionalAttrs (targetPlatform != hostPlatform && targetPlatform.libc == "msvcrt" && crossStageStatic) {
-  makeFlags = [ "all-gcc" "all-target-libgcc" ];
-  installTargets = "install-gcc install-target-libgcc";
-}
 
 // optionalAttrs (enableMultilib) { dontMoveLib64 = true; }
 )
+) [
+  (callPackage ../common/libgcc.nix   { inherit version langC langCC langJit targetPlatform hostPlatform crossStageStatic; })
+]